The invention relates to an automatic portioning and weighing arrangement for loose products, the arrangement comprising at least one store drum whereby the store drum comprises at least one portioning capacity wherein separate portions of the products may be formed and whereby the weighing arrangement comprises at least one collecting capacity. Examples of such "loose products" are popcorn, chips, french fries, sweets, pastery, small metal products or products made from a synthetic material.
Such automatic portioning and weighing arrangements may be used in automated rapid kitchens, but also in automations which may be served by means of a coin or insert piece.
Such an automatic portioning and weighing arrangement is known from the American patent specification U.S. Pat. No. 3,690,247. The store drum of this portioning and weighing device is obliquely arranged so that with a rotating drum the loose products make their way to the lowest part. The portioning capacity is at the level of this lowest part. The portioning capacity consists of parts which radially project from the jacket of the drum. With a rotating drum these parts carry each time a portion of products which is delivered somewhat further in a collecting capacity. This rotation of the drum continues until a specified weight is reached in the collecting capacity. Then the rotation stops.
This arrangement according to the state of the art, however, displays different drawbacks: First, the portioning capacity is rather small, as a consequence the chance for choking ups with the delivery of products is great. Next, a lot of space is needed around the store drum because of the structure of the portioning capacities. The weighing is also mostly inaccurate: Rest product may be wedged at the delivery valve of the portioning capacity and may, after the rotation of the store drum has ended, so after the desired weight has been reached, still fall into the collecting capacity in such a way that the eventually obtained weight is greater than the adjusted weight. Finally, the store drum is difficult to clean.
The object of the invention is to avoid the above mentioned drawbacks.
The invention provides an automatic portioning and weighing arrangement for loose products, the arrangement comprising at least one store drum whereby the store drum comprises at least one portioning capacity wherein separate portions of the products may be formed and whereby the weighing arrangement comprises at least one collecting capacity. The store drum is almost horizontally arranged and the portioning capacity extends over almost the complete length of the store drum. Hence there is a rather large portioning capacity, which makes the chance for choking ups almost non-existant.
According to a preferable embodiment, the store drum is cylindrical and the portioning capacity is completely within the circumference of the store drum. This has the advantage that the store drum takes little space.
Preferably, the portioning capacity is formed by a part of the outer jacket of the store drum and by the delivery valve. Preferably, the delivery valve is rotatable around an axle which is excentric and almost parallel to the axis of the store drum over the whole length of the store drum and the rotation of the delivery valve is commanded by means of a cam. Preferably, the arrangement is further provided with a filling valve which is rotatable around the same axle as the delivery valve and whereby the delivery valve rests on the filling valve in the delivery position. To fill the store drum the delivery valve is not in the delivery position and the filling valve is brought against the delivery valve. The advantage of such a system of valves is that there is a minimum amount of machine parts and that cleaning is easy.
According to a preferable embodiment, the portioning and weighing arrangement is further provided with an endless conveyor belt where the loose products fall on on delivery from the portioning capacity. This belt carries the products to the weighing arrangement. Such an embodiment has as an advantage that the belt functions as a kind of buffer between the store drum with the portioning capacity and the weighing arrangement : The weighing arrangement does no longer order the rotation of the store drum. Rest product falls always on the belt and not in the collecting capacity of the weighing arrangement such that accurate measurements may be done. Preferably, the circumferential velocity of the belt and the rotation of the store drum are so regulated that the belt receives one portion of loose products every half revolution.
According to another preferable embodiment, the weighing arrangement is provided with a blocking slide which may block all possible delivery of loose products to the collecting capacity of the weighing arrangement. Such an embodiment also increases the chance for accurate measurements: Once the adjusted weight has been reached, the blocking slide closes and no products, even no rest product, may enter the collecting capacity.
According to a particular and preferable embodiment, the portioning and weighing arrangement is provided with two cylindrical store drums which are in parallel positioned adjacent to one another in such a way that both may deliver portions of loose products to the same weighing arrangement. Such a positioning allows for a continuous working if one of both store drums must be filled or cleaned.
According to another particular and preferable embodiment the portioning and weighing arrangement is provided with two collecting capacities which are horizontally movable and which may serve two separate working up installations. Such an embodiment leads to an accelerated working : while the one quantity is being weighed, the other quantity may already be delivered to the working up installation.